Study On HIV-1 Subtype And Drug Resistance In Men Who Have Sex With Men In Guangzhou

Objective:To study the distribution characteristics and epidemic trend of HIV-1 subtypes and drug resistance（DR）in men who have sex with men（MSM）in Guangzhou from 2008 to 2015.Methods:Collecting serum samples from HIV-1 positive people who infected from men who have sex with men,newly confirmed or have not received antiretroviral treatment from 2008 to 2015 in Guangzhou.The virus RNA was extracted from the collected serum samples.The whole protease gene（PR）and partial reverse transcriptase gene（RT）sequence of pol region of virus RNA were amplified by nested polymerase chain reaction（PCR）.Chromas was used to edit and splice PCR products,and ML of FastTree2.1.8 was used to structure phylogenetic tree.The gene subtypes of HIV-1 and the distribution of HIV-1 gene subtypes in different years and different characteristics can be determined by phylogenetic tree.Then the sequence of the spliced sequence could be imported into the resistance sequence analysis tool of Stanford University HIV resistance database（http://hivdb.stanford.edu）to identify the resistance locus and drug resistance degree of the virus.SPSS 20 software was used to make statistical analysis of the data.Results:1.General situation: According to the selection criteria,2473 newly confirmed serum samples of HIV-1 positive antibody were successfully amplified,and 2210 copies were successfully amplified.The average age of 2210 population was 30.19 years old,mainly in young adults.The proportion of Han and unmarried population was 90.81% and 73.39%,respectively.In the newly confirmed HIV-1 positive samples,2,283 serum samples that did not receive antiviral treatment were collected,and acquired 1,986 pol region target gene fragments.The the average age of the 1986 sample population was 30.18 years old,and the ratio of unmarried and Han people was relatively high,74.17% and 90.63%,respectively.2.Distribution of HIV-1 subtypes: There are several HIV-1 subtypes in the newly confirmed HIV-1 infected people of MSM in Guangzhou from 2008 to 2015.Among them,the proportion of CRF07_BC and CRF01_AE subtypes was 38.22% and 34.49% respectively,followed by CRF55₀1B,B,URFs,CRF59₀1B and other subtypes,accounting for 14.62%,6.06%,3.58%,2.17% and 0.63% respectively.Subtypes with statistically significant constituent ratios in different years were B,CRF55₀1B,CRF07_BC and URFs subtypes.The constituent ratio of B subtype decreased year by year in 2008²015（P=0.000,99%CI:0.000⁰.000）.The constituent ratio of URFs subtype increased year by year in 2008²015（P=0.000,99%CI:0.000⁰.000）.Among the farmers,migrant workers and multiple sex partners,the proportion of URFs was significantly higher than that of non migrant workers and non sex partners.3.The prevalence of drug resistance: The total drug resistance rate of this study was 3.3%,of which the drug resistance rates of PIs,NRTIs and NNRTIs were 1.36%,0.65% and 1.61%,respectively.The resistance rate of the B subtype to three kinds of drugs was high,and the resistance rate for D4 T,EFV and NVP was the highest,all 4.17%,followed by NFV,AZT and RPV,all 3.33%.The resistance rate of CRF55₀1B to NNRTIs was higher than that of other subtypes,and the rate of resistance to EFV and NVP was the highest,which was 5.50%,followed by ETR and RPV,which were all 5.15%.Conclusion:1.The average age of HIV-1 infected people in MSM in Guangzhou was about 30 years old from 2008 to 2015,which was consistent with the results of previous studies of other provinces and cities.It suggested that young people are still the main population of AIDS prevention and control.It is necessary to strengthen health education and propaganda about AIDS in this age group.2.The composition ratio of URFs subtype in the HIV-1 infected people of MSM in Guangzhou was increasing year by year in 2008²015.It is suggested that multiple subtypes of HIV-1 have been reorganized in this population.The occurrence of this phenomenon may be related to the larger population mobility in Guangzhou and the higher ratio of MSM sex partners.We should strengthen the intervention of farmers and migrant workers and people with multiple sex partners in the Guangzhou MSM.3.The transmitted drug resistance rate of HIV-1 infected people who had not received antiviral treatment in Guangzhou in 2008²015 was still at a low level.The existing drugs are still applicable to the population in general.However,the drug resistance rate of B subtype and CRF55₀1B subtype were relatively high compared with other subtypes,which needs to be paid attention to early.